Other Names: 
bute, equiphen, phenylzone, phenylbute
Phenylbutazone (200 mg/ml) is a commonly used nonsteroidal antiinflammatory drug (NSAID) used in horses. It is available in tablet, powder, paste tube or injectable form. Phenylbutazone is a nonselective COX-inhibiting drug. Administering as a dosage of 2.2 mg/kg twice a day is considered to be a relatively safe dose for mild pain.

Phenylbutazone is one of the most popular NSAIDs used in horses, particularly in the United States, due to its low cost, ease of administration, and relatively minimal adverse effects. Phenylbutazone is a synthetic, nonhormonal antiinflammatory, antipyretic compound useful in the management of inflammatory conditions. The apparent analgesic effect is probably related mainly to the compound’s anti-inflammatory properties. It is used for the relief of inflammatory conditions associated with the musculoskeletal system.

INJECTABLE: 100 mL vials, 200 mg/mL (1 g/5 mL) Each mL contains 200 mg phenylbutazone, 10.45 mg benzyl alcohol as preservative, sodium hydroxide to adjust pH to 9.5 to 10.0, and water for injection, Q.S.

Dosage: 4.4-8.8 mg/kg, IV or PO, q12-24h